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FASC. 4. Pp. 177-213 









The Beitish Museum (Natubal Histoky), Cbomwell Road, S.W.7 


B. QcTAEiTCH, Ltd.i; Dulau & Co., Ltd. ; and The Oxford University Phkss ; 
ALSO by Ot-tvER & Boyd, Edinsurgit 


Issued 27th July, 1929.] [Price Two Shillings and Sixpence, 



Although a monograph, or series of papers, dealing comprehensively with 
the land arthropod fauna of any group of islands in the South Pacific may be 
expected to yield valuable results, in connection with distribution, modification 
due to isolation, and other problems, no such work is at present in existence. 
In order in some measure to remedy this deficiency, and in view of benefits 
directly accruing to the National Collections, the Trustees of the British 
Museum have undertaken the publication of an account of the Insects and other 
Terrestrial Arthropoda collected in the Samoan Islands, in 1924-1925, by 
Messrs. P. A. Buxton and G. H. E. Hopkins, during the Expedition of the 
London School of Hygiene and Tropical Medicine to the South Pacific. 
Advantage has been taken of the opportunity thus afforded, to make the studies 
as complete as possible by including in them all Samoan material of the groups 
concerned in both the British Museum (Natural History) and (by courtesy of 
the authorities of that institution) the Bishop Museum, Honolulu. 

It is not intended that contributors to the text shall be confined to the 
Museum Staff or to any one nation, but, so far as possible, the assistance of the 
leading authorities on all groups to be dealt with has been obtained. 

The work is divided into nine " Parts " (see p. 3 of wrapper), of which 
the first eight are subdivided into " Fascicles." Each of the latter, which 
appear as ready in any order, consists of one or more contributions. On the 
completion of the systematic portion of the work it is intended to issue a 
general survey (Part IX), summarising the whole and drawing from it such 
conclusions as may be warranted. 

A list of Fascicles already issued will be found on pp. 3 and 4 of this wrapper. 


Keeper of Entomology. 

British Museum (Natural History), 
Cromwell Road, S.W.7. 


Paet VI. Fasc. 4 

By J. E. Collin 

(With 7 Text-figures) 


Among the Diptera collected in Samoa by Messrs. Buxton and Hopkins, this 
family is represented by four species of Syneches (Hybotinae) and one of Drapetis 
(Tachydrominae). Both genera have a wide distribution, but Syneches is more 
confined to subtropical regions than Drapetis. 

Syneches Walker. 

The Samoan species of Syneches are very closely allied, and belong to a group 
having the hind femora only slightly dilated, without spines beneath, but with 
3-5 shorter or longer anteroventral bristles, and wings with the stigma not 
extending to the end of the marginal cell. The head is also more semicircular 
in profile than usual, without the flattening of the upper part so conspicuous in 
some species, and without any great difference in size, or sharply marked dividing 
line, between the upper and lower facets ; the ocellar bristles are well developed, 
but the ocellar tubercle is small ; the third antennal joint is longer than deep ; 
the thorax is strongly arched, but the arch is rounded and not pointed ; the 
disc bears scattered hairs, and there is a depression in front of the scutellum 
with a pair of strong dorsocentral bristles at the upper end of this depression 
and therefore some distance from the scutellum, this latter bearing one pair of 
VI. 4 177 1 



long bristles, and a few much shorter hairs. The prothorax above the base of 
the front coxae bears 2-3 tiny, downcurved hairs (omitted in fig. 1) instead of 
the usual upcurved one. So far as I can trace, this combination of characters 
is unusual in Syneches. 

Table of Species. 

1. (6) Disc of thorax shining black, but uniformly covered with microscopic 

brownish dust ......... 

2. (3) Hind femora not conspicuously pale about base .... alienus, sp. n. 

3. (2) Hind femora conspicuously yellowish on basal third .... 

4. (5) Hind femora with 3-4 long bristles (quite twice as long as femur 

is thick) on not more than apical two-thirds. Pterostigma 

elongate .......... devius, sp. n. 

5. (4) Hind femora with 5-6 shorter bristles (hardly longer than femur is 

thick) extending right to base. Pterostigma almost quadrate . brevispinus, sp. n. 

6. (1) Disc of thorax brightly shining black, microscopic dust limited to 

prescutellar depression, extreme front of thorax, neighbourhood 

of postalar calli, and scutellum . . . . . . sp. indet. 

1. Syneches alienus, sp. n. (Text-fig. 1). 

(J. Head : antennae below middle of head, black, clothed with brownish 
dust, arista bare. Occiput black, clothed with brownish dust, pubescence on 
upper part confined to a single postocular fringe, but spreading out in middle 
on to the more convex portion of occipital region. Proboscis tawny ; palpi dark. 

Thorax black, slightly shining from all points of view in spite of brownish 
dust ; corners of humeri and postalar calli yellowdsh. Multiserial acrostichals 
and uniserial dorsocentrals short and dark, not much longer than third antenna! 
joint ; a pair of strong dorsocentral bristles in front of prescutellar depression, 
a diagonal row of three notopleural, a smaller postalar and a pair of strong 
scutellar bristles. 

Abdomen coloured and dusted like thorax, with, in addition to the numerous 
short dark hairs, long bristly hairs on basal side margins of first segment and on 
hind margin at sides of other segments, becoming successively shorter towards 
tip of abdomen. Hypopygium small and inconspicuous. 

Legs very dark tawny, hind pair almost black, front and middle femora 
not quite so dark, front and middle tibiae and tarsi still less so, conspicuously 
clothed with brown pubescence and with following bristles : a very long, strong, 
anterodorsal bristle at basal third of middle tibia, a shorter one behind at 
middle, at tip a posteroventral spur of similar size and a shorter anteroventral 
one. Hind femora with three long, anteroventral bristles on middle half (basal 

one separated from other two), a shorter bristle in front well beyond middle, 

Text-fig. 1. — Syneches alienus, sp. n. cJ. 

and another towards tip. Hind tibiae with an anterodorsal bristle just below 
basal third, and a short, antero ventral spur at tip. In addition, a bristly hair 



both above and below at tip of front tibiae, and above at tip of four posterior 
tibiae ; three equally spaced, very short but distinct, anteroventral bristles on 
middle tibiae, and a row of fine, bristly hairs anteroventrally on hind tibiae, 
almost hidden in longer pubescence there. 

Wings slightly brownish, veins dark except at extreme base of wing. 
Stigma very distinct, somewhat quadrate, rather longer than deep, and not 
quite extending downwards to radial vein ; stigma beginning at end of sub- 
costal vein and ending farther than its own length from end of radial vein. 
First section of discal vein rather longer than next, which forms upper margin 
of discal cell. Middle cross-vein exceedingly close to pointed base of discal 
cell. Third posterior cell somewhat narrowed towards its end, omng to the 
curve of faint anal vein. End of discal cell much more than length of its 
terminal cross-vein from end of fifth vein. Halteres black, with yellow base 
to stem. 

$. Very similar in all respects to Abdomen ending in a pair of short, 
flattened, pubescent lamellae, looking like another short, narrow segment. 
Length about 2-5 mm. 
Upolu : Vailima, 3 1 26.iii.1925. 

The differences between this species and the Fijian Syneches pullus Bezzi 
{Dipt. Bmchyc. & Athene, of the Fiji Is., p. 54, fig. 17, 1928) are greater than 
the respective figures would seem to indicate. S. pullus has the upper part of 
eyes flattened and the facets on the flattened part very large — very much larger 
than those below. 

The anteroventral bristles on the hind femora are more spinose, and just 
behind these bristles (rather more beneath the femora) there is a second row of 
short spines, which is completely absent in S. alienus. Bezzi describes the 
thorax of S. pullus as " quite bare " ; this is not entirely correct, for there are 
a few tiny hairs as indicated in the figure ; but in S. alienus the hairs are 

2. Syneches devius, sp. n. 

Very much like S. alienus, but differing in colour of legs, shape of ptero- 
stigma, and length of pubescence on thorax and legs. 

Eye-facets slightly larger, but, as in S. alienus, no sharp division between 
larger and smaller facets, while latter are confined to posterior eye-margin and 
extreme lower part of eye. 



Thoracic pubescence longer, noticeably so behind the pair of strong dorso- 
central bristles. 

Legs paler ; front legs, hind trochanters and basal third to half of hind 
femora yellow, hind tarsi somewhat tawny. Pubescence longer, especially so 
behind front tibiae, behind first joint of front tarsi, behind middle tibiae (where 
some hairs stand out almost as fine bristles), and beneath hind femora 
and tibiae, some hairs beneath latter being also almost like fine bristles. 
Hind femora with an extra dorsal bristle near tip, close to the more apical of 
the two usual anterodorsal bristles. 

Wings with stigma not quite so dark as in 'S. alienus, longer and not so 
quadrate, its length fully equal to half distance along costa between subcostal 
and radial veins. Middle cross- vein about its own length from base of discal 

Length about 2-5 mm. 

Type and 4 paratypes. — Upolu : Malololelei (Buxton and Hopkins). 
Savaii : Salailua, and Safune, rain forest, 2,000-4,000 feet, v.1924 (Bryan). 

3. Syneches brevispinus, sp. n. 

Eesembling S. alienus in shortness of pubescence and shape of 
pterostigma, and S. devius in colour of legs. 

Ocellar bristles somewhat shorter than in S. alienus and very much shorter 
than in S. devius. 

Thoracic pubescence about as in S. alienus. 

Pubescence on legs shorter than in S. alienus, especially behind front tibiae 
and beneath hind tibiae. All bristles much shorter ; anterodorsal bristle on 
middle tibiae about one-third of length of that in S. alienus (only about half 
length of first tarsal joint), and bristle behind middle tibiae very short. Antero- 
ventral bristles on hind femora more numerous and short, that nearest base 
close to base of femur ; no dorsal bristle towards tip of hind femora such as is 
present in S. devius. Anterodorsal bristle on hind tibiae very short. Colour 
of legs similar to that in S. devius, but hind tibiae broadly yellow about base. 

Pterostigma quadrate, very distinct, deeper than in S. alienus ; radial vein 
curved downward opposite stigma to accommodate it, and therefore more 
undulated than in S. alienus. Middle cross- vein barely its own length from 
base of discal cell. 



Length probably about 2-25 mm. 

1 $ (type). Savaii : Safune, rain forest, 2,000-4,000 feet, 3.V.1924 (Bryan). 
This type is in the Bishop Museum, Honolulu. 

4. Syneches, sp. ? 

This species is certainly distinct from the others by reason of its more 
shining thorax and different pubescence on the legs, but the single female before 
me is much damaged and has neither wing complete, so that the necessary full 
description cannot be given. 

There is no question of dust on the thorax having been rubbed off, because 
the short dark hairs (similar in length to those of S. alienus) are present un- 
damaged. The ocellar bristles are very long as in S. devius, with which species 
it also agrees in the colour of the legs, except that the coxae and trochanters are 
all yellow. The chief difference in the leg pubescence from S. devius lies in the 
presence of still more distinct long bristly hairs behind the front and middle, 
and beneath the hind tibiae ; there are especially two long bristly hairs behind 
the middle tibiae standing out at right angles to the shaft, and antero- and 
posteroventral rows of bristly hairs beneath the hind tibiae. The remaining 
portion of one wing shows that the stigma is probably as in S. devius. 

Length quite 2-5 mm. 

Savaii : Salailua, 1 23.V.1924 (Bryan). 

Drapetis Meigen. 

The single species of Drapetis, while appearing to be congeneric with 
D. exilis Mg., exhibits certain differences some of which may be of importance. 
The second antennal joint bears a small but distinct bristle beneath, and, while 
there are two pairs of ocellar bristles, there are no vertical bristles. The eyes 
are practically in contact below the antennae. Seen in profile the head is more 
globular and the disc of the thorax less raised above the level of the prothoracic 
" collar " ; the disc is bare, and though obviously " rubbed " in all the specimens 
before me, cannot, I think, even normally be clothed as in D. exilis ; at most I 
suspect only uniserial tiny dorsocentral hairs, of which I find traces ; there 
appears to be no distinct prescutellar dorsocentral, but there is an upcurved 
humeral bristle. Venational differences include the shortness of the subcostal 
vein, which ends practically opposite the middle cross- vein ; the radial vein is 



also very short, ending very little beyond the middle of the wing, with its short 
curved prefurca arising from the subcostal vein near the end of the latter. The 
anal angle of the wing is not at all developed, and the last section of the postical 
vein is distinctly curved downwards towards the wing margin at the tip. 

5. Drapetis savaiiensis, sp. n. (Text-fig. 2). 

Frons shining black, narrowing towards front where it is almost as wide 
as second antennal joint. Eyes microscopically pubescent. Occiput clothed 
with brownish dust, but having a shining postocular ring, narrow above and 
below, but much widened in middle because of concavity of eye-margin there. 
Two pairs of long ocellar bristles, front pair parallel, hind pair divergent ; only 
fine dark hairs on vertex and back of head. Antennae with third joint slightly 
longer than first two joints together, and in addition having its upper angle 
prolonged so that it looks like base of arista ; from end of this prolongation 
proceeds at a slight angle the long microscopically pubescent arista. Palpi 
dark, small and ovate. 

Thorax black, shining and apparently bare on disc, except for postalar calli 
and scutellum, which are clothed with brownish dust. Prothorax and upper 
part of pleurae also clothed with brownish dust, leaving lower part of sterno- and 
hypopleurae shining. An upcurved humeral bristle ; a row of 3-4 bristles 
above root of wing, of which front two are stronger and probably represent 
notopleural bristles ; a small postalar, and a pair of strong apical scutellar 
bristles placed close together. 

Abdomen dull brownish-yellow and apparently not much chitinized, except 
for hypopygium, which is blacker. Pubescence short and dark, longer on 
hind margin of last tergite and on hypopygium. 

Legs, including coxae and trochanters, yellow, with apical half of hind femora 
blackish, and tibiae, especially hind pair towards tips, sometimes rather tawny ; 
last joint of all tarsi brownish. Front coxae mth a few projecting small black 
spines, including a stronger one at upper outer corner. Front femora with a 
short yellow bristle or two and a small black spine at base beneath, a short 
anteroventral row of tiny black points about base, and a posteroventral row 
of short dark bristles on apical half. Front tibiae with two short rows of tiny 
black points, anteroventrally about middle and posteroventrally towards tip. 
(Other legs in case of type too obscured by gum to describe.) 



Wings decidedly brownisli. Second basal cell ending slightly before middle 
of wing, and longer than first basal cell by about length of its terminal cross- 
vein. Cubital and discal veins nearly straight, only gradually and slightly 
diverging. Halteres yellow, with somewhat dusky knob. 

Resembling cJ, but abdomen pointed, ending in a pair of short, narrow 
papillae ; abdominal pubescence extremely short and inconspicuous. Front 

Text-fig. 2. — Drapetis savaiiensis, sp. n. Wing of (J. 

legs with less distinctive bristles, coxae with yellowish bristles of which a more 
brownish basal bristle is the most conspicuous ; femora with only 2-3 yellow 
bristles beneath at base ; tibiae apparently simple. 
Length perhaps slightly over 1 mm. 

Savaii : Salailua, rain forest, 2,000-4,000 feet, 1 (^, 1 $ (types), 23.V.1924 ; 
same locahty, 1 $ (paratype), 17. v. 1924 (Bryan). Type in Bishop Museum, 


In the material brought back from Samoa by Messrs. Buxton and Hopkins, 
the Pipunculidae are represented by two species of Pipunculus. One of these 
belongs to a small, distinct group, of which species are known to occur in Fiji, 
North Queensland and possibly Formosa ; the other, owing to the bad condition 
of the single available specimen, and our lack of knowledge of the group, 
characters for all described species outside the Palaearctic Region, cannot be 
given its correct place among those species and is left without a name. 



6. Pipunculus limitarls, sp. n. (Text-figs. 3a and 4). 

Frons and face dusted silvery-grey, former short and narrow, latter very 
little narrower below antennae, and gradually narrowing below until it is about 
half width of front of frons (text-fig. 3a). Occiput dusted greyish, less so 
above. Eye-facets not enlarged in front. Antennae yellow, third joint pale 
yellow, short and small, with bluntly pointed tip. 

Text-fig. 3. — Pipunculus limitaris, sp. n., ^ (a) ; P. vitiensis Muir, (J (b), $ (c). Heads viewed 

from in front. 

Thorax shining black, but slightly obscured all over with brownish dust ; 
a vertical band on middle of pleurae has a tendency to yellowish-brown ; tiny 
hairs on dorsum apparently confined to dorsocentral rows, with some slightly 
longer ones at sides of disc and round scutellar margin. 

Abdomen almost parallel-sided (slightly wider towards end), translucently 
dirty yellowish on first three or four segments, but everywhere, including long 
fifth segment and large hypopygium, covered like thorax with a thin layer of 
brownish dust. Two or three yellowish-brown bristles on each basal angle of 



first (visible) segment, pubescence otherwise short and pale, becoming a little 
longer towards tip. Hypopygium slightly inclined towards right, with a very 
large terminal depression (text-fig. 4). 

Legs entirely yellow, hind coxae perhaps a little brownish about base. 
Tibiae without spurs. Front femora with a few posteroventral, minute black 

points towards tip, middle femora with 
similar antero ventral and (more extended) 
posteroventral points, hind femora with 
only hairs instead. Only hind femora 
shining behind. 

Wings with venation almost exactly 

as in P. vitiensis Muir (text-fig. 5), costal 

Text -FIG. 4. — Pimmculus liinilaris, st>. n. - t_ j. ^ e t j.- i 

... f ^ 1 i 1 • segment between ends oi mediastmal 

Abdomen or (J, lateral view. 

and radial veins equal in length to the 
following segment, stigma not reaching back to end of mediastinal vein, and 
bounded basally by a distinct cross-vein. End of subapical (or first posterior) 
cell, perhaps not quite so wide as in P. vitiensis. Halteres and squamae yellow. 
Leng-th about 2-5 mm. 

Samoa : 1 ^ (type). Tutuila : Afono Trail, 1 ^ (paratyjje), 25.ix.1923 
(Swezey). Type in Bishop Museum, Honolulu. 

Text-fig. 5. — Pipunculus vitiensis Muir (Fiji). Wing of cj. 
The shading of the stigma (cf. text-fig. 6) is accidentally omitted. 

P. limitaris is closely allied to P. heterostigmus Perkins (North Queensland) 
and P. vitiensis Muir (Fiji). All three species agree in the peculiar venation, 
especially the abbreviated stigma, bounded basally by a distinct cross-vein, 
and in having an indistinctly translucent yellow base to the abdomen. 

P . heterostigmus has darker legs, " the femora largely darkened above and 
at the sides " in the female, and only " the trochanters, knee joints and tarsi 



mostly yellowish " ; in the with " the tibiae for some part more brown." * 
The costal segment between the ends of the mediastinal and radial veins is 
distinctly longer than the next, as can be seen in text-fig. 6, a drawing made 
from the type and kindly supplied by Dr. 0. H. Swezey. 

P. vitiensis, the type and $ of which, through the kindness of Dr. Swezey, 

Text-fig. 6. — Pipunculus heterostigmus Perkins (N. Queensland). Wing of type. 

I have been able to examine, has yellow legs like P. limitaris, but the has a 
narrower face (text-fig. 3 6); a few of the front facets of the eyes below the 
antennae are distinctly enlarged even in the the disc of thorax is more sliining, 
with a tendency for the sides and scutellum to be yellowish, and the hypopygium 
seen from the side is much smaller (text-fig. 7). The frons of the $ (text-fig. 3 c) 
is very much wider below than above, transversely convex, and sliining black 
except right in front, where it is clothed 

with greyish dust, the dusting being 
continued for some considerable distance 
backwards along the eye margins. The 
female hypopygium may be somewhat dis- 
torted in the type, but the oval basal part 

is yellowish on its outer side and black on ^ext-fig. l .-Pifunculus vitiensis Wuiv 
the side nearest the venter, while the (Fiji). Abdomen of lateral view, 
yellowish aculeus is as long as this basal 

part, laterally compressed, slender and gradually tapering, and arises from the 
basal part with rather a distinct break on the side nearest the abdominal venter. 

P. bicolor Becker, a Formosan species described in 1924, probably belongs 
to this group ; it has the abdomen shining yellow and an abbreviated stigma, 
though no mention is made of a cross- vein at its base. 

* Perkins pointed out the possibility that the two sexes may belong to distinct species. 



The cross- vein at base of the stigma, which, is very distinct in most of the 
foregoing, may be more or less evident in other species ; even the European 
P.flavipes shows some indication of it, while both P. abdoniinalis Lw. (Caffraria), 
a species with yellowish sides to the abdomen, and P. semiopacus Lamb 
(Seychelle Is.) appear to show an indication of this character in a darkening of 
the basal margin of stigma. In all these three species, however, the stigma 
extends back to the end of mediastinal vein, a fact which appears to make the 
abbreviation of the stigma in P. heterostigmus and its allies a character of greater 
value than the presence of a cross-vein. 

In view of my belief that the species of Pipunculus may be divided into 
two groups by the presence or absence of a propleural fan of hairs in front 
of the lower end of the prothoracic spiracle, it is worth recording that such a 
fan is present in at least P. limitaris and P. vitiensis. 

7. Pipunculus, sp. ? 

A single in bad condition, without antennae, appears to resemble 
P. homoeophanes Perkins, of N. Queensland. The frons is dusted at the sides, 
but shining black about the middle. Thorax black, with disc dusted brownish 
though still slightly shining, pleurae and metanotum clothed with greyish dust ; 
tiny dorsocentral hairs uniserial, a few longer hairs behind darkened humeri, 
and very tiny ones on margin of scutellum. Propleural fan present. Abdomen 
much wider in middle than at tip, first segment mainly grey with a single bristle 
on each upper basal angle, second to fifth segments with dull black basal cross 
bands, those on second and third segments narrower at sides than in middle 
where they nearly reach hind margin, those on fourth and fifth segments more 
even in depth, fourth about two-thirds and fifth one-half depth of segment, 
rest of middle segments clothed with brownish-grey dust (browner at sides), 
hinder half of fifth segment shining black with sides clothed with brownish dust. 
Hypopygium small, clothed with brownish-grey dust, with a moderate-sized 
terminal depression. Legs (in specimen before me mainly buried in gum with 
which insect is secured to its mount) apparently dark, with base and tip of at 
least four posterior tibiae yellowish, and possibly tarsi pale. Wings brownish, 
stigma complete, third costal segment equal to fourth, upper outer corner of 
discal cell opposite point in costa just beyond end of subcostal vein ; middle 



cross-vein at rather more than two-fifths of length of discal cell. Halteres 
pale, with dusky base to stem and extreme tip of knob. 
Length very little more than 2 mm. 

Savaii : Safune, lower forest, 1,000-2,000 feet, 1 v. 1 924 (Bryan). 


Text-fig. 1. Syneches alievMS, sp. n. ^. 

„ 2. Drapetis savaiiensis, sp. n. Wing of ^. 

„ 3. Pipunculus limitaris, sp. n., ^ (a) ; P. vitiensis Muir, ^ (b), $ (c). Heads viewed 
from in front. 

,, 4. Pipunculus limitaris, sp. n. Abdomen of ^, lateral view. 

5. Pipwiculus vitiensis Muir (Fiji). Wing of type ^. 

„ 6. Pipunculus heterostigmus Perkins (N. Queensland). Wing of type. 

„ 7. Pipunculus vitiensis Muir (Fiji). Abdomen of type (J, lateral view. 


By Frank M. Hull, Texas State Experiment Station, College 
Station, Texas, U.S.A. 

(With 2 Text-figures.) 

The insular distribution of Syrphid flies is nowhere of greater interest than in 
the Bast Indian and South Pacific regions, and I wish to express my thanks to 
Mr. P. A. Buxton, through whom I am able to present the following studies of 
the Samoan S3rrphid fauna. An analysis of material from this region is 
rendered the more interesting in view of the publication of certain dipterological 
studies of the Fiji islands by the late Dr. Mario Bezzi {Diptera Brachycera and 
Athericem of the Fiji Islands, 1928). The Samoan Syrphids show a marked 
similarity to that of the Fijian group. Eleven species, belonging to ten genera, 
were recorded from Fiji, and the present pa.per lists ten species (one hundred and 
forty-five specimens), representing nine genera ; eight of the Samoan species 
were found also in Fiji. Moreover, in both archipelagos an unusually high 
percentage of species fall within the subfamily Syrphinae. It is certainly 
peculiar that the island regions, Samoa, Fiji, and New Zealand, as far as present 
records show, should contain markedly high Syrphine components, in contrast 
to especially low ones in the case of such islands as Sumatra, Borneo, Java and 
Celebes. The average for the latter region is about 18 per cent., and for the 
former as high as 66 per cent., with the highest of all represented by 70 per cent, 
in Samoa. Finally, it may be remarked that Eristalinae and Milesiinae seem 
to predominate farther to the north-west. The Samoan Syrphids are of Malayan 
origin, five of the ten species occurring also on the Asiatic mainland. 


1. Melanostoma univittatum Wied. 

Sixty-two specimens from the following localities : 

Upolu : numerous examples from Apia, Afiamalu, Vaea, Vailima, Malolo- 




lelei, collected in iii, iv, v, vi, vii, ix, xii (various collectors). Savaii : Safune 
and Salailua, iv and v.1924 (Bryan). Tutuila : Pago Pago, ix and xii. There 
is also one from Tonga (Vavau, Neiafu), 5. iii. 1925 (Hopkins). 

2. Asarcina ericetorum Fabr. var. oceanica Bezzi. 

Bezzi {Dipt. Brachycera and Athericem of the Fiji Islands, p. 71, 1928) 
describes only the One can infer that, since the hair on the frons is black, 
the ground colour is also black. This is the case with all of the present series. 
The scutellum is mainly black-haired. 

Savaii : Salailua, 4 16-24.V.1924. Tutuila : Pago Pago, 1 ^, 2 
12-16.iv.l924 (Bryan), and 23.ix.1923 (Swezey and Wilder). Upolu : Apia, 
1 5.iv.24 (Armstrong) ; Vailima, 1 

3. Syrphus corollae Fabr. var. vitiensis Bezzi. 

In some cases a small spot continues the yellow thoracic stripe to the 
scutellar margin. The colour of the abdominal bands is more brownish-orange 
than yellow. 

Tutuila : Fagasa, 4 1 9.ix.l923 (Swezey and Wilder). Upolu : 
Apia, Aleipata, I ^,2 iv. and v.1924, 1925 (Buxton and Hopkins). Savaii : 
Safune, lowlands to 1,000 feet, 1 1. v.1924 (Bryan). There is also one $ 
from Tonga, Vavau (Haloga), 23.ii.1925 (Hopkins). 

4. Ischiodon scutellaris Fabr. (Text-fig. 1). 

Three five The males agree quite well with typical specimens. 
Bezzi {ojp, cit. p. 73) states that the anterior eye facets are not enlarged in this 
species, but in the males from Samoa, the facets are very distinctly enlarged in 
the region to the side and just above the base of the antennae. Brunetti 
{Fauna of British India, vol. 3, p. 97, 1923) likewise finds the anterior facets 
enlarged. The anterior tarsi are not blackened at the tips but reddish in colour. 
In two of the three males the genitalia, though strongly developed and visible 
above, are shining black, but in the third they are reddish. The spine on the 
trochanters is stout. The five females vary considerably. The dark area of 
the scutellum is much deeper and more distinct, and the abdominal bands on 



the third and fourth segments are quite narrow, either interrupted or nearly so, 
and do not approach the anterior margin. In one specimen, however, the 
yellow bands on the third and fourth segments are contiguous as described for 
typical examples, but the fifth segment has, instead of a black transverse band, 
an obscure brownish spot on either side. Most of the females have the fifth 

Text-fig. 1. — I sehiodon scutellar is Fahi. ^. 

segment wholly shining black, with narrow posterior margins and small anterior 
corners obscurely shining brownish. 

Upolu: Malololelei, 3 19.iv, (Armstrong). Tutuila, 

2 <$<^, 25-30.ix.l923 (Swezey and Wilder). There are also 1 c^, 2 from 
Tonga (Vavau, Haloga), 9.iii.l925 (Hopkins). 

5. Xanthogramma javanum Wied. 

Three from Tutuila, Savaii, and Upolu. Owing to the black-haired 
scutellum and the reversed coloration of the hind tibiae, this species is readily 
distinguishable from Ischiodon scutellaris Fabr. The third joint of the antennae 
is about as broad as long, rounded at the tip, and brownish-orange in colour, 
VI. 4 2 



smoky on the dorsal half. In the specimens from Tutuila and Savaii the ground 
colour of the scutellum is clear opaque yellow. 

Tutuila : Pago Pago, 1 14.xii.l92o (Buxton and Hopkins). Upolu, 1 
7.vii.l925 (Wilder). Savaii : Safune, 1 $, 5.V.1924 (Bryan). 

'. ' ' 6. Xanthogramma amphoterum Bezzi. 

Bezzi's series of specimens of this species came from Movua and Lautoka,, 
Fiji, and fxom Rarotonga. The present collection includes a male and female 
which show several noteworthy differences from the type. 

(J. Shining black borders to third and fourth abdominal segments quite 
narrow, posterior borders about five times as broad as anterior, on the anterior 
margins of these segments the shining portion limited to a very narrow band. 

In this specimen the velvety black bands on the third and fourth 
abdominal segments are broader than in the male ; in the type, according to 
Bezzi, the reverse is the case. There is no trace of the anterior shining band. 
Moreover, the yellow transverse bands on these segments, instead of being entire, 
are widely interrupted and broken up into spots. The individual before me 
may represent a distinct species. However, in its ensemble of characters, 
X. amphoterum is supposed to be intermediate between Ischiodon scutellaris 
Fabr. and Xanthogramma javanum Wied. var. distinctum Kertesz. In default 
of a series of the forms involved, anything in the shape of a definite conclusion 
is impossible. Other slight departures from the type are as follows : the 
antennal prominence is clothed with yellow instead of black hair ; the sides of 
the face are not whitish but sulphur yellow, and their pile is pale ; the third 
antennal joint in the male is rather light yellow and as long as broad, with its 
tip somewhat truncated. 

Tutuila : Pago Pago, 1 18.iv.l924. Savaii : Safune, lowlands to> 
1,000 feet, 1 4.V.1924 (Bryan). 

7. Baccha praefica Bezzi (Text-fig. 2). 

The present collection includes a number of examples of this interesting 
species, which was described by its author (op. cit., p. 76, 1928) from the female 
alone. I therefore give a description of the male below. The female specimens 
show slight differences from the Fijian material. The short hairs on the front 



(frons) and sides of the face are pale instead of dark. The second and third 
abdominal tergites especially have a purplish lustre mingled with the blue ; 
this likewise shows faintly on the dorsum of the thorax. The scanty blackish- 
brown dust on the thorax is disposed in such a way that anteriorly three very 
narrow shining stripes may be seen in some lights. So strong is the metallic 
coloration, however, that these are not visible in every specimen. 

Vertical triangle very acute, wedge shaped, about four times as long as 

Text-fig. 2. — Baccha praefica Bezzi. $. 

wide, with a longitudinal crease or impression anteriorly, and the short black 
bristles set in a row arranged antero-posteriorly. Front with long, stiff, shining 
black, bristly hairs. Upper anterior eye facets barely perceptibly enlarged. 
Second joint of antenna showing same inner protuberance as in Hypopygium 
small and shining black, not visible from above, 

Upolu : Malololelei, 9, 7.vii.l924 (Armstrong, Buxton 
and Hopkins). Savaii : Safune and Salailua, 1 cJ, 3 21, 22.V.1924. Tutuila : 
Pago Pago, 4 c^(^ (cotypes), 1 16-18.iv.l924 (Bryan), 14.xii.l925. 




8. Volucella obesa Fabr.* 
Upolu, 5 (^(^, 9 o?, 15.iii-vi., xii.1925. Tutuila, 1 ^, 18.iv.l924 (Bryan). 


9. Dissoptera maritima sp. n. 

Four males of this peculiar fly included in the present collection present 
important differences from D. unicolor Bezzi, to which, owing to its general 
dark coloration, the species would appear to be related. The antennae are 
black, not reddish, and the arista, which is scarcely longer than the entire 
antenna, is very strongly thickened on its basal half or two-thirds. The 
yellowish scaly tomentum is not at all apparent, although some short yellowish 
hair is present beneath the longer black vestiture. The halteres are yellowish, 
and the male genitalia slightly visible from above. There are some long pale 
hairs on the hind femora, especially about the tips, as well as the denser, stiff, 
semi-appressed black bristle-like hairs. The wing-veins are brownish, and the 
costa ends approximately at the tip of wing. Bezzi states that the eyes of 
D. unicolor are unicolorous, but in all four specimens before me I can observe 
well-defined, small, point-like spots or reflections, suggesting the appearance 
afforded by certain females of Lathy rophthalmus. 

^. Eyes bare, separated widely, as described for Z). unicolor, narrowest in 
profile on lower half ; distance between eyes at lower part of front but slightly 

* This species frequented earth closets, and was observed to deposit its eggs on the under 
side of the seat. — P. A. Buxton. 

Possibly owing to the agency of old-time sailing ships, to which it may have been attracted 
by odours, Volucella obesa has a wide distribution in the tropics, where it occurs in both hemi- 
spheres. As shown by the series of specimens in the British Museum, apart from Samoa the fly 
is found at any rate in Mexico, Central and South America, the West Indies, the Sandwich Is., 
Tahiti, Rodriguez I., Mauritius, the Seychelles Is., Madagascar and N. Nigeria (the National 
Collection includes a solitary specimen from Kano). On the Lower Amazons, Brazil, thirty-odd 
years ago, it was " very common everywhere," and its association with privies was also noted. 
" Like the Bee {Chrysantheda nitida), which it closely resembles when on the wing, this fly is the 
victim of an overpowering curiosity, and remains poised in the air in front of one in a way that 
is perfectly irritating. It seems to be an exceedingly stupid fly, and when caught in the net its 
movements at once become dull and sluggish " {cf. Austen, Proc. Zool. Soc. Lond. 1896, p. 776). 
— B. B. Austen. 



greater than at vertex. Front just before antennal prominence shining black, 
bare ; remainder of front and vertex shining metalhc bhiish, largely obscured 
by brownish-black dust ; front and vertex completely covered with rather 
thick, long, shaggy, black hair, extending to upper occiput ; behind black hair 
a narrow band of whitish hair of similar length. Upper occiput very prominent, 
so that corners of eyes are cut away posteriorly ; middle of occiput devoid of 
long hair, with microscopic whitish pubescence and whitish pollen, and with a 
few longer white hairs below. First and second joints of antennae shining 
black, third joint opaque black, rounded, slightly deeper than long. Arista 
black, bare, much thickened on basal half. Face depressed immediately below 
antennae, otherwise strongly projecting ; shining black, covered along eye 
margins, narrowly opposite side of antennae, more widely below to middle of 
cheeks, with dense white band of microscopic pubescense, connected just below 
antennae. Shining black middle of face with a few longer black hairs, sides 
sparsely clothed with long white hairs. 

Dorsum of thorax shining black, narrowly opaque anteriorly, and clothed 
with thick, long, greyish hair, which becomes black in middle and posteriorly. 
Scutellum black, shining, clothed with very long, black hair. Pleurae grey, 
feebly shining, \vith middle covered with dense tufts of long, greyish- white pile. 
Halteres light yellowish. 

Abdomen shining black, with nearly parallel sides, third and fourth segments 
being only slightly narrower than second, and with their sides very strongly 
incurved. Dorsum clothed with rather long, thick hair, becoming shorter 
posteriorly, whitish on second and third segments anteriorly, forming a black 
band posteriorly ; fourth tergite with entirely black, appressed, stifiish hair. 
Genitalia shining black, short, black haired, and barely visible from above. 

Legs slender, shining black (except tarsi, which are dark brown), clothed 
for most part with black hair ; a few whitish hairs on anterior tibiae posteriorly, 
and both long, sparse, white hairs and microscopic whitish pubescence on hind 
femora : first joint of hind tarsi slightly thickened. 

Wings hyaline ; stigma and veins light brown, costa ending a little before 
tip of wing. 

Upolu : Malololelei, 1 (holotype), 2.vii.l924 (Armstrong), 1 (paratype), (Buxton and Hopkins). Tutuila : Pago Pago, 2 <^(^ (paratypes), 
18.iv.l924 (Bryan), 14.xii.l925. 



r 10. Lathyrophthalmus nitidus Van der Wulp. 

The Samoan variety of this striking species agrees in detail with Bezzi's 
description of Fijian specimens {ajp. cit., pp. 79-80, 1928), except that the anterior 
border of the second abdominal segment in the female is interrupted in only 
one instance ; the median interruption of the bands on the following segments 
is quite characteristic. 

Upolu: Malololelei, 1 8 (Armstrong), 7.vii.l925 

(Wilder). Tutuila : Pago Pago, 1 9.ix.l925 (Swezey and Wilder). Savaii : 
Safune, 1 ^, 16.V.1924 (Bryan). 


Text-Jfig. 1. Ischiodon scutellaris Fabr. ^. 
„ 2. Baccha pmefica Bezzi. 


By J. R. Malloch, Bureau of Biological Survey, Washington, D.C., U.S.A. 

(With 6 Text-figures.) 


In 1925 Melander and Argo {Proc. U.S. Nat. Mus., Vol. 64, Art. 11, pp. 1-54, 
Pis. 1-4, 1925) published a revision of this family, and included in their paper 
keys to all the recognized genera and species of the world. They recorded the 
fact that no species had then " been described from Africa, Australia, or Asia," 
while only four of the eighty known species " have been recorded from the 
islands south of Asia." Since the appearance of that paper I have described an 
Australian species, and more recently Bezzi {Diptera Brachycera and Athericera 
of the Fiji Islands, p. 87, 1928) described one from a solitary specimen from 
Fiji. Both of these species belong to the genus Meter omeringia Czerny, which 
was previously known to be represented in North and South America, and in 
Europe. In the Samoan material I find examples of two species which are not 
referable to any known genus, and are therefore described below. 

The species of which the life-histories are known live in the larval and pupal 
stages in dead wood, some of them under the bark of recently felled trees, others 
in rotten portions of growing trees, and still others in much decayed, spongy 
areas in dead tree-stumps or logs. Usually the flies may be found on the trunks 
of trees suitable for their oviposition and especially on fallen timber, but unless 
searched for in such situations they are seldom met with, and thus are much 
rarer in collections than is the case with some other families which are more 
promiscuous in their flight habits. Neither in their immature nor mature stages 
are the species of economic importance to man. 

Isoclusia, gen. n. 

This genus has two pairs of reclinate orbital bristles, no cruciate inter- 
frontals, ocellars and postverticals present, equal in length, and shorter than 




anterior orbitals ; arista very short haired ; vibrissae single, situated behind 
anterior line of eyes, and very widely separated ; thorax with 1-2 pairs of 
dorsocentrals, four scutellars, one mesopleural and one sternopleural ; all tibiae 
with a preapical dorsal bristle, very short and fine on hind pair ; first wing-vein 
bare ; ultimate section of fourth vein about five times as long as penultimate 

In the key given by Melander and Argo {loc. cit., p. 4) this genus cannot be 
carried further than (2), since it can be placed in neither of the groups segregated 
by the characters listed, one having reclinate orbitals and cruciate interfrontals, 
and the other having either proclinate or convergent anterior orbitals. 

Genotype, Isoclusia samoaensis, sp. n. 

1. Isoclusia samoaensis, sp. n. 

Shining tawny yellow, face whitish-yellow, with white dust ; frons 
brownish, orbits narrowly margined with whitish dust ; antennae and palpi 
testaceous yellow ; legs entirely yellow ; wings hyaline, with a fuscous cloud at 
tip from apex of second vein, evanescent posteriorly. 

Frons dull, subquadrate, interfrontalia bare, anterior orbital with a very 
slight curve at apex, about half as long as posterior orbital ; eyes almost round, 
bare ; third antennal segment about 1-5 as long as wide, rounded at apex ; 
arista slender, about 1 -5 as long as width of anterior margin of frons ; cheek 
about as high as width of third antennal segment ; face slightly convex. 
Thorax with four series of intradorsocentral hairs, presutural bristle well 
developed, and no distinct prescutellar acrostichals ; scutellar bristles subequal, 
disc bare. Legs normal, front femur with a series of posteroventral bristles, 
becoming longer apically. Outer cross-vein of wing set over 1-5 its own length 
from apex of fifth vein ; ultimate section of fourth vein about five times as 
long as penultimate section, not noticeably curved forward apically. 

Length, 3 mm. 

Savaii : Safune, type and paratype $, 13.V.1924 (Bryan). Type in the 
Bishop Museum, Honolulu. 

2. Isoclusia hyalipennis, sp. n. 

c^. Very similar in all respects to the foregoing species, and agreeing in 
colour and general structure, but with no trace of an apical dark mark on the 


wings. Upper surface of fore tarsi with erect, curled, black hairs, distinctly 
longer than diameter of segments upon which they are situated ; outer cross- 
vein in wing about half its own length from inner one. 
Length, 3 mm. 

Upolu : Afiamalu, type 7.xi.l925 (Wilder). This specimen is in the 
Bishop Museum, Honolulu. 

Even allowing for the contingency of sexual dimorphism, it would appear 
impossible that the forms described above are the male and female of the same 
species, the cases where wing-markings are absent in one sex and present in the 
other being normally the reverse of that exhibited here. More material, in 
much better condition, is, hoAvever, required before a definite decision can be 


In the work to which reference has already been made. Dr. Bezzi did not 
attempt to place the Fijian species in their proper genera, as distinguished in 
the recent papers by Dr. F. Hendel and myself ; and without access to his 
species it is impossible to decide the exact status of all of them. It is, however, 
evident from Bezzi's statement that all of the species placed by him in Sapro- 
myza have the small black setulae on the costal vein extending to the end of 
third vein, that all are referable to the genus Homoneura van der Wulp sens, 
lat. Whether the species belong to several subgenera can only be determined 
by an examination of the type specimens, but it appears probable that Sapro- 
myza acrotoxa Bezzi is a Griphoneuroides. Griphoneura insignis Bezzi is very 
probably referable to the same subgenus of Homoneura, since no true species 
of Griphoneura is yet known to occur in the Orient. 

The peculiar Fijian genus Encyclosis Bezzi is not represented among the 
Samoan material before me. 

Bezzi was in error in placing three Fijian species in Drosomyia de Meijere. 
The species in question belong to Trypaneoides Tonnoir and Malloch, a genus 
found in Asia, and extending southward to New Zealand. I have examined the 
genotype of Drosomyia, and find that it lacks the discal bristle on the mesopleura 
which characterizes Trypaneoides. 



Trypaneoides Tonnoir and Malloch. 

In a recently published revision of the Oriental Sapromyzidae,* I have 
dealt with the species of this genus, with the exception of one which occurs in 
Australia, and another which is found in New Zealand. None of the three 
Pijian species assigned by Bezzi to Drosomyia agree with any of those in my 
key. All three of them run to No. 7 in that key, and all have but one clear 
spot on the costa between the ends of the second and third veins, being thus 
distinguished from T. hyalipuncta Malloch. In Sapro?yiyza leucostica Bezzi 
there is but one spot, or two connected spots, in the apex of the first posterior 
cell, a character which readily distinguishes this species from all the others, in 
which there are eight or more such spots in that cell ; in S. cirrhicauda Bezzi 
there are about twelve clear spots in the first posterior cell, owing to those in 
the apical half of the cell being divided by a dark line ; and in S. caniventris 
Bezzi the spots in the same cell are all more or less connected by pale lines 
extending between them on the central line of the cell. 

In the material from Samoa I find examples of one of the species described 
by Bezzi, and of two others which are distinct from his. Below I present a 
key for their differentiation. 

Key to the Species. 

1. Face densely covered with pale grey, with two complete, rather broad, dark 
brown transverse bands, one a little above lower margin, the other 
below bases of antennae ; longest hairs on arista about five times as 
long as its basal diameter ; cheek without a dark mark near vibrissal 
angle ; ultimate section of fourth wing vein very distinctly less than 
twice as long as penultimate section ; large species, averaging over 
4 mm. in length . . . . . . . . ... caniventris Bezzi. 

Face covered with grey dust, with at most a narrow, dark, transverse 
band near lower margin, sometimes reduced to three dark spots, one 
on each side, the other in centre ; hairs on arista not, or very slightly, 
longer than its basal diameter ; ultimate section of fourth vein 
twice as long as penultimate section ; smaller species, not over 3 mm. 
in length . . . . . . . , . . . . ,, . .2 

* Cf. Malloch, J. R., " Notes on Some Oriental Sapromyzid Flies (Diptera), with Particular 
Eeference to the Philippine Species " : No. 2751, Proc. U.S. Nat. Mus., Vol. 74, Art. 6, pp. 1-97, 
Pis. 1-6, 1929. 



Cheek without a dark spot near vibrissal angle ; three clear spots and a 
central longitudinal streak in submarginal cell of wing (between 
apical sections of veins 2 and 3) ; Eijian species .... 

Cheek with a black-brown spot near vibrissal angle ; submarginal cell of 
wing with clear spots, with or without longitudinal central streak 

Only three clear spots in submarginal cell of wing ; no clear spot on each 
side of inner cross- vein ; ground colour dark brown 

More than three clear spots in submarginal cell of wing, the additional 
spots rather small and faint ; a clear spot on each side of inner cross- 
vein ............ puncticeps, sp. 

leucosticta Bezzi. 

samoaensis, sp. n. 

3. caniventris Bezzi. 

This species, besides its larger size and the distinctions mentioned in the 
above key, has the frons more protuberant in front, and two or more out- 
standing discal bristles on the mesopleura. 

Length, 4-6 mm. 

Upolu: Apia, 31.V.1924 ; Vailima, Tutuila : Pago Pago, 
4.xi.l925 (Buxton and Hopkins) ; and Leone Road, 19.ii.l924 (Bryan). Manua : 
Tau, 20.ii.l926 (Judd). Tonga Islands : Vavau, Neiafu, 5.iii.l925 ; Nukualofa, 
22.ii.1925 (Hopkins). 

Judging from its occurrence in these three groups of islands, this species 
would appear to be the most widely distributed of those found in this region, 
but it may be that its larger size is responsible for its more frequent inclusion 
in collections. 

3a. Trypaneoides leucosticta (Bezzi). 

I accept as belonging to this species one specimen before me, despite certain 
differences between it and Bezzi's description and figure. It is possible that the 
faint longitudinal streaks in the marginal, submarginal, and first posterior cells 
of the wing in my specimen are evident because the example is rather teneral, 
since they do not show in Bezzi's figure. There is a marked distinction between 
the specimen before me and Bezzi's description, the former having the abdomen 
pitchy black, with two round white pollinose spots on each side of each tergite 
except the basal one, situated about midway between the fore and hind margins, 
and a smaller white pollinose spot in the middle of the hind margin. Bezzi, on 
the other hand, describes the species as having the paired spots on the hind 
margin, and the central one on the fore margin. Unless we have examined 



different species, I can only assume that there is an error in Bezzi's description 
reversing the position of the white spots.* ' ' 

; Length. 3 mm. 

Fiji Islands : Viti Levu, Colo-i-Suva, (Bryan). 

This species, which is not known to occur in Samoa, is included here because 
of the above-mentioned points of variance with the original description and 
figure. It has not been previously recorded from this locality in Fiji. 

4. Tr^aneoides samoaensis, sp. n. (Text-fig. 1). 

Black, densely clothed with brownish-grey dust. Interfrontalia fuscous ; 
face with three small, dark brown, almost connected marks in depression above 

Text-fig. 1. — Trypaneoides samoaensis, sp. n. Wing. 

lower margin, and a similarly coloured mark between antenna and eye ; a 
black-brown mark on each cheek near vibrissal angle ; antennae brownish- 
yellow, third segment black except upper basal angle ; aristae and palpi fuscous 

* A careful comparison of the example from Colo-i-Suva, Viti Levu, Fiji, here discussed by 
Mr. Malloch, with the type (J and $ of Sapromyza leucosticta Bezzi, shows conclusively that the 
three specimens are conspecific. In all three the colour of the abdomen is the same (dark mummy- 
brown) ; the paired spots are not on the hind margins of their respective tergites, but are nearer 
to the hind than to the fore margins ; and the small median spot on the fore margin of the third 
and fourth tergites in the case of the ^ type, and at least on that of the third tergite in the 
specimen examined by Mr. Malloch, extends on to the hind margin of the preceding tergite. As 
regards the wings, the pale longitudinal streaks which, as stated by Mr. Malloch, are present in 
the dark areas in the marginal, submarginal and first posterior cells in the case of the specimen 
from Colo-i-Suva, would appear to be due to individual variation, if not to immaturity as Mr. 
Malloch suggests. As a matter of fact, the distal portion of the first posterior cell in the case of 
Bezzi's (J type shows a trace of such a streak, which is more evident in the left wing than in the 
right. — E. E. Austen. 


Thorax with four pairs of acrostichals and dorsocentrals ; mesopleura with one 
strong discal bristle. Mesonotum with following dark brown marks : a pair of 
vittae between acrostichals and dorsocentrals, broken at third pair of dorso- 
centrals, and widened behind to enclose prescutellar acrostichals ; a pair of 
interrupted vittae between dorsocentrals and lateral margin, and a large spot 
at base of each bristle ; pleurae largely spotted with dark brown ; scutellum 
without dark spots. Abdomen with numerous small and moderately large 
spots of pale dust on dark brown ground, each hair and bristle inserted in one 
of the pale spots, largest of latter in a series near posterior margin, and one in 
centre of anterior margin, of each tergite. Legs testaceous yellow, with dark 
bases to femora, a dark mark near tip of each femur, and one near base of each 
middle and hind tibia. Wings as shown in text-fig. 1. Ultimate section of 
fourth vein twice as long as penultimate. Halteres dark brown. 
Length, 3 mm. 

Tutuila : Pago Pago, 1 (type), 14.xii.l926 (Buxton and Hopkins). 
In all three of the small species the halteres are dark, in T. caniventris they 
are yellow. 

5. Trypaneoides puncticeps, sp. n. (Text-fig. 2). 

A darker coloured species than the foregoing, with which it agrees in 
structure and size. The covering of dust on the head and thorax is leaden 

Text-fig. 2 — Trypaneoides puncticeps, sp. u. Wing. 

grey, that on the abdomen yellowish-grey. The face has the lower dark mark 
forming a complete band, and the thoracic dorsum has the submedian vittae 
much broader and complete, connecting, or almost connecting, with two dark 



stripes on the scutellum. Legs as in T. samoaensis, but the femora are fuscous 
except at the tips. Wings as shown in text-fig. 2. 

Upolu : Tuaefu, type and allotype, 16.ix.l923 (Swezey and "Wilder). 
Type in the Bishop Museum. 

Homoneura van der Wulp. 

This is the predominant genus of the family in the Malayan region, and 
apparently in Oceania also if one may judge from the material already described. 
In Australia Sapromyza Fallen is the richest in species ; although many of the 
forms are rather aberrant, it is not possible to distinguish them generically in a 
satisfactory manner at this time. I have erected several subgenera of Homoneura 
in the paper referred to above, and two of the segregates named therein are 
represented in the Samoan material before me. 

Bezzi has described three Fijian species, which belong to a group in which 
but one sternopleural and no intra-alar bristle is present, the anterior one of the 
three pairs of dorsocentrals is presutural, and the mesonotum is metallic bluish 
or greenish. This group is unrepresented in the Samoan material now before 
me. All the other Fijian species included in Bezzi's key after the foregoing 
three are said to have a distinct intra-alar bristle, and would therefore be assign- 
able to the subgenus Minettioides Malloch, but none of them agrees with any 
one of the species of this subgenus dealt with below. 

I have before me a male and female from Fiji (Viti Levu), which appear to 
belong to H. ensifem Bezzi, but they are teneral and it is impossible to be certain 
as to this. The female possesses a knife-like ovipositor, and in other respects 
the species agrees very well with the description except that the specimens are 
darker than described. The particular point, however, that I desire to mention 
is that the specimens do not possess a well-developed intra-alar bristle as 
required by Bezzi's key, and it is possible that an error has crept in here. Since 
the species is not Samoan, I do not care to deal further with it here. 

It must be noted that Bezzi, in considering the length of the hairs on the 
arista, takes the total extent from the tips of the hairs on the lower side to the 
tips of those on the upper side, thus making any estimate he gives twice as 
great as that given by me, since I consider only the length of the individual 

I present below a key to the Samoan species, only two of which fall within 
any of the segregates in Bezzi's key. 


Key to Species. 

1. A small but distinct intra-alar bristle on mesonotum (Subgenus 

Mineltioides Mallocb) . . . . ■ . . . . . . . .2 

No distinguishable intra-alar bristle (Subgenus Homoneum van der 

Wulp) 4 

2. Abdomen with two series of deep black, round spots, one pair on 

each tergite from second, or third, to sixth inclusive ; ^ hypo- 

pygium yellow ............. 3 

Abdomen with three series of black, more or less angular spots, 
lateral spots connected with a black hind marginal fascia which 
extends to, or almost to, extreme lateral margin of tergites 3 to 
6 inclusive, spots sometimes enlarged to form three broad black 

vittae ; hypopygium of (J black or fuscous .... nigricauda, sp. n. 

3. Fore femur without a series of stifE black spinules on apical half of 

antero-ventral surface ........ apiseriata, sp. n. 

Fore femur with a series of stifi black spinules on apical half of ante- 

roventral surface ......... setulosa, sp. n. 

4. No well-developed acrostichal bristles in front of prescutellar pair ; 

thorax largely grey ........ hawaiiensis Mai loch. 

One or more pairs of well-developed acrostichal bristles in front of 

prescutellar pair ............. 5 

5. Shining black species, anterior margin of frons reddish, abdomen 

glossy black ; halteres with fuscous knobs .... anthracina, sp. n. 
Shining yellow species, only black markings consisting of some black 
spots on apical half of dorsum of abdomen, usually three on 
fifth and two on sixth tergite, with more rarely three much 

fainter ones on fourth ; halteres yellow ..... acrostichalis de Meijere, 

6. Homoneura acrostichalis de Meijere. 

This species is readily distingmshable from its allies by the presence of a 
fringe of closely placed, small black setulae along the sides of the sixth abdominal 
tergite, on the extreme edge, in the ^. The fore femur has the usual series of 
very small black spines on the apical half of the anteroventral surface, a 
character which distinguishes the species in both sexes from others of similar 
general appearance occurring in the same region, several of these lacking the 
series which is normally present in this genus throughout the Orient. 

Tutuila : Amauli, (Swezey and Wilder) ; Pago Pago, 18.iv. 
(Kellers). Upolu : Apia, 27.V.1924 (Bryan). Manua : Tau, 20.V.1926 (Judd). 

H. acrostichalis also occurs in the Dutch Indies, and Formosa. 



7. Homoneura (Homoneura) hawaiiensis Mallocli. 

Distinguishable at once from any other species represented in the collection 
before me owing to the thorax being densely covered with grey dust. As its 
name implies, the present species was originally described from material from 
Hawaii, where, so far as my existing knowledge goes, there is only one other 
representative of the genus. 

Tutuila : Pago Pago, 14.xii.l925. Upolu : Apia, 18.ii.l924 (Buxton and 
Hopkins), and 27.V.1924 (Bryan). Savaii : Safune, 5.V.1924 (Bryan). Manua : 
Tau, 20.ii.l926 (Judd). 

I have seen examples of this species from no other localities than Samoa 
and Hawaii. 

. " 8. Homoneura (Homoneura) anthracina, sp. n. (Text-fig. 3). 

Glossy black ; anterior margin of frons, and usually most of face and 
cheeks, antennae, trochanters, tibiae, and tarsi, testaceous yellow ; palpi, 
antennae, and face, sometimes brown or fuscous. Wings greyish-hyaline, not 
blackened at bases. Calyptrae and knobs of halteres fuscous. 

Frons parallel-sided, a little longer than wide, orbital stripes slightly differ- 
entiated, orbital bristles moderately strong, anterior pair a little shorter than 
posterior pair, ocellars and postverticals shorter than anterior orbitals, sub- 
equal, outer verticals over half as long as inner pair ; longest hairs on arista 
about equal in length to its basal diameter ; third antennal segment over 1-5 
as long as wide ; face shining. Thorax with usual three pairs of postsutural 
dorsocentral bristles ; intradorsocentral hairs in about ten series, and at least 
one pair of outstanding acrostichal bristles about midway between suture and 
hind pair ; sternopleurals 2. Abdomen ovate ; male hypopygium as in text- 
fig. 3. Fore femur with series of short setulae on apical half of antero ventral 
surface quite well developed ; middle tibia without posterior bristles ; liind 
femur without an anteroventral preapical bristle ; preapical dorsal bristle 
present on all tibiae. Inner cross-vein of iving slightly proximad of middle of 
discal cell ; penultimate section of fourth vein fully two-thirds as long as 
ultimate section. 

Length, 3-5-4-5 nun. 

Tutuila : Pago Pago, type allotype, and 3 paratype 14.xii., 1925 (Buxton 



and Hopldns) ; paratype 9, and 1 paratype pair in copula, same locality, 
25.ix.1923 and 24.ix.1923 respectively (Swezey and Wilder). 

In Tahiti there is a somewhat larger species, very closely related to this but 
distinguished by structural differences. It is still undescribed, but I hope very 
shortly to include it in a report on material from that region. 

9. Homoneura (Minettioides) nigricauda, sp. n. (Text-fig. 4). 

This and the two following species are very similar in colour and general 
habitus. A description of the present species will suffice for the others, of 
which only distinguishing characters will be mentioned. 

Shining orange-yellow. Frons as in H. anthracina, dull, slightly darker 
in the centre ; longest hairs on arista about three times as long as its basal 
diameter. Thorax as in H. anthracina, but with about eight series of intra- 
dorsocentral hairs, and no well-developed acrostichals except prescutellar pair. 
Abdomen with three series of black, more or less triangular marks, varying much 
in intensity and development, central series sometimes indistinct and lateral 
ones and apical fascia much reduced ; in darker examples black markings 
forming three broad, complete vittae from near base to apex of abdomen. 
Hypopygium as in text-fig. 4, generally black or fuscous, rarely yellow^ in part. 
Legs yellow ; fore femur with preapical anteroventral series of setulae very 
fine and hair-like, almost undeveloped ; all tibiae with preapical dorsal bristle. 
Wings as in H. anthracina, yellowish hyaline. Halteres yellow. 
VI. 4 3 


Text-fig. 3. — Homoneura anthracina, sp. n. ^ hypopygium. 
Text-fig. 4. — Homoneura nigricauda, ,, ,, ,, 
Text-fig. 5. — Homoneura apiseriata, ,, ,, ,, 



Length, 5 mm. 

Savaii : Safune, type and 4 paratypes, 17-23. v.1924 (Bryan). Tutuila : 
Afono Trail, 1 paratype, 25. ix. 1923 (Swezey and Wilder). Type in Bishop 
Museum, Honolulu. 

An example with yellow hypopygium and no central black spots on the 
abdomen appears to represent a pale form of this species. The specimen shows 
the lateral apical fascia extending from the sublateral spot to the lateral extremity 
of the tergites of the apical half of the abdomen, a character which distinguishes 
it from the next two species. ^ 

Tutuila : Pago Pago, 1 9. i v. 1924 (Bryan). The specimen is in the Bishop 

10. Homoneura (Minettioides) apiseriata, sp. n. (Text-fig. 5), 

(^$. Similar to H. {M.) nigricauda, and differing only in having a pair of 
round black spots on each tergite from third to sixth inclusive, and in the outer 
arms of the hypopygium having a more decided projection at the apex {cf. text- 
fig. 5). 

Length, 5 mm. 

Upolu : Tuaefu, Sliding Rock, type allotype, 1 paratype and 1 para- 
type 16.ix.l923 (Swezey and Wilder). Type in Bishop Museum. 

In the case of the two paratypes there is a slight indication of a darkened 
central spot on the anterior margin of some of the tergites of the apical half of 
the abdomen. 

11. Homoneura (Minettioides) setulosa, sp. n. 

Slightly paler in colour than species 9 and 10, with the round, black, 
paired spots on the abdomen beginning on the second visible tergite, and the 
fore femur with a distinct comb -like series of minute black spines on the apical 
half of the anteroventral surface. In other respects as H. {M.) apiseriata. 
Length, 5 mm. 

Manua : Tau, type, 20. ii. 1926 (Judd). In the Bishop Museum, Honolulu. 

Panurgopsis Kertesz. 

I consider Prucliaetofs Bezzi {Diptera Brachycera and Athericera of the Fiji 
Islands, p. 120, 1928) identical with this genus. Bezzi states that his genus is 



distinguished from Panurgopsis by the anterior orbitals being directed back- 
wards, and by the presutural bristle being stronger ; but his figure {op. cit., p. 
122, fig. 38) shows the anterior orbitals curved inwards at the tips as in Panur- 
gopsis. The strength of the presutural bristle is of little importance in this 
group ; only its total absence is worth considering as a generic criterion, and 
even where it is normally absent it is sometimes weakly represented. 

In the paper dealing with Oriental Saproniyzidae which is referred to on 
p. 201 above, I have included a synopsis of the genera related to Panurgopsis, 
and the Samoan species run satisfactorily to it in the key. 

In the Samoan material there appear to be representatives of only one 
rather variable species, which is described below as new. 

12. Panurgopsis quadriseriata, sp. n. 

(^$. Pale testaceous yellow, slightly shining. Frons at vertex about one- 
third as wide as head, its length about 1 -5 as great as its width, hairy in front, 
and with bristles as in P. (Prochaetops) nigriseta Bezzi, postverticals well below 
vertex, in other respects as that species. Ocellar spot black, a dark brown 
mark between each antenna and eye, and sometimes two small dark dots on 
centre of labrum. Thorax with dorsum largely fuscous, with a broad pale 
central vitta extending over apex of scutellum and centre of postnotum, lateral 
margins of mesonotum yellow, dark sublateral portions varying from brown to 
blackish, always darker along pale stripe ; sternopleura with a dark mark on 
upper anterior portion : 1 -|-2 dorsocentrals, intradorsocentral hairs biseriate, 
sternopleurals 2 ; scutellum slightly flattened on disc. Abdomen ovate, with 
four series of black dorsal spots on anterior margins of tergites, faint in immature 
examples. Legs normal, yellow. Wings as in P. nigriseta, hyaline. Halteres 
with yellow knobs. 

Length, 3-3'5 mm. 

Savaii : Salailua, rain forest, 2,000-4,000 feet, 1 type, 17.V.1924 (Bryan). 
Safune, lower forest, 1,000-2,000 feet, allotype and 1 ^ paratype, 4.V.1924 
(Bryan). Tutuila : Leone Road, paratype 19.ii.l924 (Bryan). Upolu, 
paratype 9, Type in the Bishop Museum. 

The last-mentioned specimen is immature and lacks definite dark spots on 
the abdomen. 



The Fijian species P. nigriseta Bezzi has a large, blackish, central spot on 
the lower margin of the face, and the fore legs from the tips of the femora to 
those of the tibiae black or fuscous. 

Trigonometopus Meigen. 

The single species of this genus represented in the collection before me is 
practically normal as regards generic characters, the face receding greatly 
below, and the presutural (posthumeral) bristle being absent, or represented by 
a short setula. I am unable to identify this species among those already 
described, and therefore consider it new to science. Although not recorded by 
Bezzi as occurring in Fiji, the genus is found in Europe, North and South America, 
Asia, man}' of the islands between that continent and Australia, and also in 
Australia itself. 

13. Tngonometopus semibrunnea, sp. n. (Text-fig. (i). 

(^$. Testaceous yellow, slightly shining. Frons over twice as long as its 
width at upper angles of eyes, clothed with hair throughout entire length in 
centre, and entire width in front, ocellars and postverticals small ; face much 

Text-fig. 6. — Trigonometopus semibrunnea, sp. a. Wing. 

receding below, epistoma in profile about middle of head, antennae normal ; 
arista pubescent. Ocellar spot brown, sometimes a similarly coloured central 
streak extending from it to anterior margin of frons ; occiput fuscous except 
on each side of central dark mark, a dark brown mark between each antenna 
and eye ; antennae brownish testaceous ; arista black ; palpi testaceous yellow ; 



all cephalic hairs black. Thorax as in genotype, but presutural bristle some- 
times weakly represented ; intradorsocentral hairs in 6-8 series. Thorax largely 
fuscous, mesonotum with a central vitta, varying in width, extending over disc 
of scutellum, and usually a narrow vitta anteriorly along each series of dorso- 
central bristles, testaceous yellow ; sutures of pleurae pale. Abdomen rather 
stout, hypopygium of ^ prominent ; dorsum fuscous, a central pale vitta may 
be complete or evident only at base, or at base and apex ; venter, including 
broadly incurved portions of tergites, testaceous yellow. Legs normal, entirely 
testaceous. Wings as shown in text-fig. 6, hyaline, deep brown along entire 
costa, shading off at fourth vein, both cross-veins narrowly clouded with brown. 
Halteres testaceous yellow, knobs fuscous. 
Length, 5 mm. 

Tutuila : Pago Pago, type ^, 14.xii.l925. Upolu : Vailima, allotype, 
12.xii.l925 ; same locality, paratype ^, 2.ii.]925 ; Malololelei, 2,000 feet, 
paratype ^, 20. vi. 1924 (Buxton and Hopkins) ; Tuaefu, paratype 16.ix.l923 
(Swezey and Wilder). Savaii : Safune, rain forest, 2,000-4,000 feet, paratype 
2.V.1924 (Bryan). 


Text-fig. 1. Trypaneoides samoaensis, sp. n. Wing. 
„ 2. ,, puncticeps, sp. n. Wing. 

„ 3. Homoneura anthracina, sp. n. (J hypopygium. 
,, 4. ,, nigricauda, sp. n. ,, 

„ 5. ,, apiseriata, sp. n. ,, 

,, 6. Trigonometopus seniibrunnea, sp. n. Wing. 





Part I. Orthoptera and Dermaptera. 

„ II. Hemiptera. 

„ III. Lepidoptera. 

IV. Coleoptera. ; 

,, V. Hymenoptera. 

„ VI. Diptera. 

„ VII. Other Orders of Insects. 

„ VIII. Terrestrial Arthropoda other than Insects. 

„ IX. Summary and Index. 

The work is published at intervals in the form of numbered fascicles. 
Although individual fascicles may contain contributions by more than one 
author, each fascicle is so arranged as to form an integral portion of one or 
other of the Parts specified above. 

List of Fascicles issued to 27th July, 1 929 ; 

Insects of Samoa and other Samoan Terrestrial Arthropoda. Maps 1 and 
2 (in envelope). 1927, 4to. 6d. 

Part I. Orthoptera and Dermaptera. 
Fasc. 1. Dermaptera. By Dr. Alfredo Borelli. Pp. 1-8. 1928, 4to. !». 
Fasc.2. Orthoptera. By Dr. L. Chopard. 51 text-figures. Pp. 9-58. 1929,4to< 5s. 

Part II. Hemiptera. 

Ease. 1 . Fulgoroidea. By F. Muir. 25 text-figures. Psyllidse (Chermidae). By 
Prof. D. L. Crawford. 4 text-figures. Coccidae, Aphididee and Aleyrodidae. 
By F. Laing, MA., B.Sc. 3 text-figures. Pp. 1-45. 1927. 4to. 2s.6d. 

Fasc.2. Cercopidae. By V. Lailemand, M.D, 10 text-figures. Cicadidae. By 
J. G. Myers, Sc.D. 22 text-figures. Aquatic and Semi-aquatic Heteroptera. 
By Prof. Teiso Esaki. 6 text-figures. Pp. 47-80. 1928, 4to. 2t.6d. 

Part III. Lepidoptera. 

Fasc. 1. Butterflies of Samoa and some neighbouring Island-groups. By G. H. E. 
Hopkins, M.A., F.E.S, 1 text-figure and 4 plates. Pp. 1-54. 1927, 4to. 5». 

Fasc.2. Micro-Lepidoptera. By Edward Meyrick, B.A., F.R.S. Pp. 65-116. 
1927, 4to. 2,.U 

Fasc. 3. Geometridae. By Louis B. Prout, F£.S. 2 text-figures and 1 plate. 
Pp. 117-168. 1928. 4to. 2>.6d. 

Date Issued, 
26th February, 1927. 

2SthJuIy, 1928. 
26th January, 1929. 

25th Juue, 1927. 
23rd June, 1928. 

9ih April, 1927. 
2Sth May, 1927. 
24th March. 1928. 

List of Fascicles issued to 27th July, 1929 {continued):— 

Part IV. Coleoptera. 

Fasc. 1. Girabidae. By H. E. Andrewes. 9 text-figures. Dytiscidae. By A. 
Zimmennann. 2 text-figures, Staphylinidae. By M. Gimeron, M.B. 2 text- 
figures. Hjjdrophilidae. By A. d'Orchymont. I text-figure Clavicomia and 
I^mellicornia. By G. J. Arrow. 13 text-figures. Pp. T-66. 1927, 4to. 3s. 

Fasc. 2. Heteromera, Bostrychoidea, Malacodermata and Buprestidae. By K. G. 
Blair, B^c. 14 text-figures. Elateridae. By R. H. van Zwaluwenberg. 10 
text-figures. Melasidae (Eucnemidas). By E. Fleutiaux. CerambycidBE. By 
Chr. Auriviilius. 1 plate. Brentnidae. By R. Kleine. 4 text-figures. 
Anthribidae. By Karl Jordan, Ph.D. 1 1 text-figures. Proterhinidae. By 
R. C. L. Perkins. DSc, F.R.S. Pp. 67-174. 1928, 4to. 5s. 

Fasc. 3. Throscidae. By K. G. Blair, B.Sc. 1 text-figure. Chrysomelidae. 
By S. Maulik. M.A. 18 text-figures. Pp. 175-215. 1929, 4to. 2s. 6<f. 

Fasc. 4. Platypodidae and Scolytidae. By C. F. C. Beeson, D.Sc. 13 text- 
figures. Pp. 217-248. 1929, 4to. 2s. U 

Part V. Hymenoptera. 

Fasc. 1. Apoidea, Sphecoidea, and Yespoidea. By R. C. L. Perkins, D.Sc, 
F.R5., and L. Evelyn Cheesman, F.E.S., F.Z.S. 12 text-figures. Larridae. 
By Francis X. Williams. 12 text-figures. Formicidx. By Dr. F. Santsclii. 
9 text-figures. Pp. 1-58. 1928, 4to. 5s. 

Part VI. Diptera. 

Fasc. 1. Streblidae and Nycteribiidae. By L. Falcoz. 7 text-figures. Hippo- 
boscidse. By G. F. Ferris. 6 text-figures. Pp. 1-21. 1927, 4to. 2s. 6d. 

Fasc. 2. Nematocera. By F.W.Edwards, MA. 20 text-figures. Cecidomyiinae. 
By H. F. Barnes, BA, Ph.D. 4 text-figures. Pp. 23-108. 1928. 4to. 5s. 

Fasc. 3. Stratiomyiidae, Tabanidse and Asilidae. By Gertrude Ricardo. 6 text- 
figures. Larvae of Stratiomyiidae. By P. A: Buxton, M A. 2 text-figures. 
Dolichopodidae. By C. G. Lamb, Sc.D. 8 text-figures. Sarcophagidas. By 
P. A. Buxton, M.A. 9 text-figures. Muscidae. By J. R. Malloch. 
Pp. 109-175. 1929. 4to. 5s. 

Fasc. 4. Empididae and Pipunculidae. By J, E. Collin. 7 text-figures. 
Syrphidae. By Frank M. Hull. 2 text-figures. Clusiidae (Heteroneuridae) 
and Sapromyzidae. By J. R. Malloch. 6 text-figures. Pp. 177-213. 1929, 
4to. 2s. 6rf. 

Part VII. Other Orders of Insects. 

Fasc 1. Isoptera : Family Termitidac. By Gerald F. Hill. 14 text-figures and 
I plate. Odonata. By Lt.-Col. F. C. Fraser, LM5., F.ES. 5 text-figures. 
Pp. 1-44. 1927. 4to. 2s. 6i. 

Fasc 2. Plectoptera. By R. J. Tillyard, Sc.D. (Cantab.). F.R.S.. and J. A. 
Lestage. 2 text-figures. Siphonaptera. By P. A. Buxton, MA. Thysanoptera. 
By Richard S.Bagnall.F.R.S.E.,F.L.S. 6text-figure». Pp.45-76. 1928. 4to. 
2s. 6d. 

Fasc, 3, Mallophaga. By J. Waterston, DSc. 2 text-figures Anoplura. By 
P. A. Buxton. MA. Trichoptera, By Martin E. Mosely. 1 figure. 
Neuroptera. By P. Esben-Petersen. 1 text-figure and 2 plates. Apterygota. 
By George H. Carpenter. D Sc, 32 text-figures. Pp. 77-1 16. 1928,4to. 2s.6rf. 

Part VIII. Terrestrial Arthropoda other than Insects. 

Fasc. 1. Isopoda Terrestria. By Harold G. Jackson. DSc. 2 plates. Scor- 
pionoidea. By P, A, Buxton, MA. Pseudo-scorpiones. By A. Kastner. 1 1 
text-figures. Acarina. Br Stanley Hirst. 2 text-figures. Pp. 1-27. 1927. 
4to. 2s. 6d. 

rase. 2. Myriopoden (Myriopoda). By C, Attems. 4 text-figures. Araign^es 
(Araneida). ByDr.LucienBerland. 79 text-figures, Pp, 29-78, 1929,4to. Is.dd. 

Date Issued. 

\9th December, 1927. 

25th February, 1928. 
23rd February, 1929. 
22nd June, 1929. 

25th February, 1928. 

23rd July, 1927. 
23rd June, 1928. 

WthMay, 1929. 
27 th July, 1929. 

2Sth May, 1927. 
23rd June, 1928. 
28th July, \92S. 

23rd July, 1927. 
22nd June, 1929.